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<!-- /* Style Definitions */ p.MsoNormal, li.MsoNormal, div.MsoNormal {mso-style-parent:""; margin:0cm; margin-bottom:.0001pt; mso-pagination:widow-orphan; mso-hyphenate:none; font-size:12.0pt; font-family:"Times New Roman"; mso-fareast-font-family:"Times New Roman"; mso-ansi-language:EN-US; mso-fareast-language:AR-SA;} @page Section1 {size:612.0pt 792.0pt; margin:70.85pt 70.85pt 70.85pt 70.85pt; mso-header-margin:36.0pt; mso-footer-margin:36.0pt; mso-paper-source:0;} div.Section1 {page:Section1;} --> Ubiquitous networks which can be accessed at any time form any place and using a range of devices are base of new kind of commerce. Commerce that offers unique and personalized service to every customer individually using ubiquitous networks is called u-commerce. U-commerce is abbreviation that stands for ubiquitous commerce, also called ubicomp or ultimate commerce or pervasive computing. U-commerce is combination of e-commerce, m-commerce, television, voice and silent commerce. It can be seen as extension of current types of commerce, but not as their replacement. Main u-commerce characteristics are described using the four u-constructs: ubiquity, universality, uniqueness, and unison. Although u-commerce brings many benefits the principal obstacle to u-commerce development and adoption are customer concerns for their privacy protection